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A free, fun platform for learning modern cryptography

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Learn By Doing

Learn about modern cryptography by solving a series of interactive puzzles and challenges. Get to know the ciphers and protocols that secure the digital world by breaking them.

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Level Up

Earn points by solving challenges. Finish categories to earn trophies and gain levels to track your progress. Can you reach the top of the scoreboard?

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Fresh Challenges

We are constantly creating new challenges to keep your crypto knowledge up to date. Expect exciting brainteasers and whole new categories as the site continues to grow.

New Challenges
Blind (ECSC 2023 (Norway)) CTF Archive 0
WOTS Up (ECSC 2023 (Norway)) CTF Archive 0
Irish flan (ECSC 2023 (Norway)) CTF Archive 0
WOTS Up 2 (ECSC 2023 (Norway)) CTF Archive 0
Twist and shout (ECSC 2023 (Norway)) CTF Archive 0
Weekly Top Users
#1 C3POlukky 6640
#2 Denys 2175
#3 urmastoobal 1890
#4 eleemosynator 1860
#5 pinvlad228 1780
Recent Solves
Factoring st4rg4z3r
RSA Starter 6 st4rg4z3r
RSA Starter 5 st4rg4z3r
RSA Starter 4 st4rg4z3r
RSA Starter 3 st4rg4z3r
Recent Solutions
Oofbleck (Firebird Internal CTF) ConnorM 0
RSA Starter 4 Ubertech 0
Modes of Operation Starter d3af90d 0
ECB CBC WTF pedropiin 0
No Leaks dtpt 0

Level Up

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